Structural Design And Performance Analysis Of Porous Radial Gas Bearing

Gas bearing is an important component of high-speed pneumatic turbine.Its support stiffness and motion stability have an important impact on the spraying quality of automobile panels.Currently,orifice compensation gas bearings are used in high-speed pneumatic turbines.There are some problems such as small stiffness and poor stability during use.Combining with the research task of Tianjin science and technology research project,this paper focuses on the fabrication technology of porous materials and the structural design and test method of high-speed gas bearing based on porous materials,aiming to improve the comprehensive performance of high-speed gas turbine device.The main research work is as follows:In order to study the pressure distribution of porous gas bearings,a mathematical model of gas pressure distribution in the clearance of radial bearings was established based on one-dimensional analysis of fluid flow in porous materials.In the process of solving the mathematical model,Newton iteration method is used to solve the pressure distribution equation,central difference method is used to discretize the solution equation,and a set of solving algorithm is compiled by using MATLAB software.By solving the equation,it is proved that the pressure distribution equation is simple,convenient and convenient for fast calculation.In the analysis of performances of porous radial gas bearings,based on the traditional structure of porous gas bearings with equal thickness,a design method of grooving on the outer side of porous materials is proposed,and numerical simulation and performance comparison of single groove and double groove structures are carried out.Based on the pressure distribution equation of single and double grooves,the pressure and moment of bearing clearance in the two structures are simulated and analyzed,and the effects of film thickness and groove width on the static performance of bearings are analyzed.In order to verify the theoretical analysis results,based on the relationship between gas bearing load and film thickness,an experimental system for measuring the load of porous gas journal bearings is designed.The experimental system includes the bearing film thickness measurement system and the loading force control system.The experimental results show that the porous graphite gas journal bearing with double grooves structure has higher load-carrying capacity and stiffness,which verifies that the theoretical double grooves structure has higher load-carrying capacity and stiffness.